/Engine/Source/Runtime/Experimental/Chaos/Public/Chaos/Collision/PBDCollisionConstraint.h
Contact constraints are allocated on the heap (Asee FCollisionConstraintAllocator) and have permanent addresses. They use intrusive handles to reduce unnecessary indirection.
class FPBDCollisionConstraint : public [Chaos::FPBDCollisionConstraintHandle](API\Runtime\Chaos\Chaos\Collision\FPBDCollisionConstraintHandle)
FVec3f
AccumulatedImpulse